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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,815 
Suppose you have a ferromagnet with relative magnetic permeability μ.And it is sittuated in a magnetic field B.
What...

Oct1811 12:33 PM
alex.rechilie

0 
758 
How is that when:
A wagon collides with the velocity (v) with another wagon (at rest, v=0) of the same mass (m) on...

Oct1811 12:10 PM
RobinSky

8 
1,456 
Hi all, if I have the velocities and rotations of an object with respect to a moving frame.
Are there relations that...

Oct1811 10:55 AM
chrisbaird

3 
1,997 
hey guys can anyone pls say how much current in amps does a ordinary car battery of 12v generates?? pls......

Oct1811 09:50 AM
JeffKoch

14 
1,609 
Consider a brickshaped ferromagnetic of relative magnetic permeability µ >> 1, which has dimensions 2a × 2a × a and a...

Oct1811 08:23 AM
alex.rechilie

0 
807 
Hi everyone,
I have a problem that I hope someone can help me with, the question is.
A mass of 500kg induces a...

Oct1811 08:13 AM
Rastanking

0 
589 
Hi,
I'm having some trouble about the calculation of saros cycle in example 13.9 of Greiner's book "classical...

Oct1811 04:26 AM
babylonia

0 
559 
Hi,
I don't understand what the offdiagonal terms in the moment of inertia (tensor) matrix are intuitively....they...

Oct1711 06:03 PM
TGlad

11 
3,347 
Hi everyone,
Well everything is in the title. Answers are not clear on the net and I cannot figure it out myself.

Oct1711 05:56 PM
atyy

7 
1,867 
For a process at constant pressure, ΔH=q.
My textbook clearly says that the only way that enthalpy can change is...

Oct1711 05:50 PM
Andrew Mason

9 
12,274 
So, in a physics lab I TA, we are doing a lab in which part of it, the students try to do Faraday's Ice Pail...

Oct1711 02:49 PM
elegysix

10 
1,917 
Hi,
first sorry for my bad English, I am more skilled to read than to write in English
I don't know if this is the...

Oct1711 02:40 PM
elegysix

3 
1,252 
This is related to Goldstein Exercise 328. It is not really a homework problem anymore because I have solved them....

Oct1711 02:35 PM
yenchin

1 
1,595 
For electrostatics, I know that conductors have 0 electric field inside. And I know that the surface of a spherical...

Oct1711 01:15 PM
chrisbaird

1 
1,223 
I was looking at some sliding doors and thinking/reviewing about the concept of work.
So I have a few questions
...

Oct1711 12:18 PM
chrisbaird

5 
1,241 
I am a bit confused about a statement I read in my textbook saying the sum of external forces on a body is equal to...

Oct1711 12:15 PM
freemovement

11 
2,175 
Hey, all!
Browsing around the library for some mechanics books, I happened to come across Manuel Prieto Alberca's...

Oct1711 12:07 PM
Metaleer

11 
1,527 
Hello everybody, I have a question about the Fresnel equations at normal incidence. My textbook gives the reflection...

Oct1711 11:19 AM
brianpile

5 
3,388 
Hello
I have found in some text books that the magnetic scalar potential is continuous across a boundary. Now, how...

Oct1711 07:37 AM
baggiano

2 
1,577 
I am trying to understand why work is a scalar, without knowing ahead of time that work is defined as:
W_{ab} =...

Oct1711 06:43 AM
Delta˛

29 
4,766 
Hi all.
I want to create a Cooler for my CPU to better overclocking
Because heat has a negative affect on cpu...

Oct1711 03:23 AM
Lsos

8 
1,958 
A little curiosity here. In my Electricity and Magnetism class, for the first half of the semester we were taught...

Oct1711 02:21 AM
Philip Wood

5 
1,237 
Need to calculate motor size to drive skip dolley system. have the following:
Frame on 6 wheels. Gearbox/motor...

Oct1711 01:01 AM
Inenzo

2 
1,050 
Hi,
I have a fairly simple question, but I am a newbie. I have to move a tricycle from one position to another....

Oct1611 11:18 PM
elegysix

1 
789 
Hello, I am currently trying to come up with an idea for a project for my advanced physics lab. I have thought to do...

Oct1611 11:09 PM
elegysix

2 
1,370 
Suppose I have acceleration defined as a function of position, "a(x)". How to convert it into a function of time...

Oct1611 10:16 PM
Ken G

2 
1,623 
The power stored in an inductor is E=0.5LI2 which is independent of frequency
However, the impedance is ωL.
So, what...

Oct1611 09:01 PM
Born2bwire

5 
3,472 
When swimming underwater, why does sound from above the surface sound very faint?
I know that the answer to this...

Oct1611 04:27 PM
Bobbywhy

2 
1,030 
Useful equation.
Avg. Power
p(t)=(V^2(t))/R
My attempt at instantaneous power was
p(t,V,R)= ∫(0>1 for t...

Oct1611 04:27 PM
Petyab

2 
767 
I do not understand this one step in deriving the angular momentum theorem for a system of particles.
The vector...

Oct1611 02:05 PM
Xyius

2 
620 
Basically, I am parallel capacitor.
First thing i am confused about how are electrons transfer so that the plates...

Oct1611 01:31 PM
fahad12

0 
530 
Here is an experiment I found on youtube:
http://www.youtube.com/watch?v=grJYxdJVTZ4
Here is how I understand...

Oct1611 09:44 AM
A.T.

17 
4,797 
Why is the change in potential energy the NEGATIVE of the work done by a force? What is the negative sign doing...

Oct1611 04:32 AM
aker221

8 
7,032 
As a quick heads up, I'm buried over my head in an imager project, and the portion that has given me the most headache...

Oct1611 01:58 AM
Mike_In_Plano

2 
867 
suppose rain water is being collected in bucket. does the rate at which it fill depend on wind?

Oct1611 01:03 AM
Mike_In_Plano

3 
1,475 
A professor the other day used an induction coil power a crt tube like the one at the link below.
...

Oct1511 11:51 PM
Mike_In_Plano

1 
1,403 
I want to verify the mechanism to which a varying E can induce voltage into a shielded coax.
According to Maxwell
...

Oct1511 11:45 PM
Mike_In_Plano

3 
1,415 
Hello. So: Why does magnetic force tend to increase magnetic energy?
1) Usually, forces go in the direction of energy...

Oct1511 11:32 PM
Mike_In_Plano

2 
1,035 
Hello, So I have a question about electric power lines.
Today I was under some large power lines and I noticed...

Oct1511 11:22 PM
Mike_In_Plano

3 
1,447 
I am new to lasers. In the expression for q parameter, 1/q = 1/R  j(λ/πw^2)
how did we come to know that w(z) is a...

Oct1511 10:20 PM
wukunlin

3 
1,532 